| Similarity | Rank | |
|---|---|---|
| SO2 | 0.733 | 90224 |
| CO. | 0.727 | 42846 |
| TCE | 0.706 | 83931 |
| NOx | 0.698 | 55787 |
| Sulphur | 0.683 | 56277 |
| Methane | 0.682 | 69623 |
| Radon | 0.671 | 60232 |
| Dioxide | 0.666 | 69551 |
| Colo. | 0.664 | 33472 |
| radon | 0.663 | 32433 |
| CO2 | 0.661 | 9992 |
| Nitrogen | 0.656 | 45976 |
| NH | 0.655 | 20228 |
| Sulfur | 0.654 | 70589 |
| WY | 0.653 | 60155 |
| ozone | 0.653 | 18222 |
| OH | 0.648 | 12637 |
| MO | 0.648 | 18569 |
| methane | 0.644 | 19799 |
| C02 | 0.643 | 94587 |
| Hanford | 0.638 | 69636 |
| Ozone | 0.634 | 41186 |
| AZ | 0.633 | 16767 |
| Loveland | 0.632 | 58641 |
| ionization | 0.632 | 60226 |